Backwater valve with control linkage

ABSTRACT

A backwater valve has a valve body, and a valve member pivotally movable about a pivot axis between an open position away from the valve body and a closed position covering the valve body. A control linkage is provided with at least one of a float or a counterweight in communication with the valve member via the control linkage to modify operation of the valve member.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/820,137, filed Nov. 21, 2017, which is a continuation of U.S. patentapplication Ser. No. 13/885,902, filed Jun. 6, 2013, issued as U.S. Pat.No. 9,863,134 on Jan. 9, 2018, which is a National Stage ofInternational Application No. PCT/CA2011/050712, filed Nov. 16, 2011,which claims priority to Canadian Application No. 2722310, filed Nov.16, 2010, all of which are incorporated herein by reference.

BACKGROUND

U.S. Pat. No. 5,406,972 (Coscarella et al.) relates to a backwater valvewhich prevents a backflow of sewage into a home.

SUMMARY

There is provided a backwater valve, comprising a hollow valve bodyhaving an inlet and an outlet, and a valve member pivotally movableabout a pivot axis between an open position away from the inlet and aclosed position covering the inlet. A control linkage is provided withat least one of a float or a counterweight in communication with thevalve member via the control linkage to modify operation of the valvemember.

The addition of a control linkage which is independent of the valvemember provides a number of advantages, whether the valve is one that isnormally in the open position or normally in the closed position. Forthe valve member that is normally in the open position, a counterweightcan be added to the control linkage to maintain the valve member in theopen position, a float can be added to the control linkage to float thevalve member from the open position to the closed position or both canbe added to the control linkage. For the valve member that is normallyin the closed position, the sensitivity of the valve member to moving tothe open position can be adjusted by adding a counterweight to thecontrol linkage.

In a preferred embodiment which will hereinafter be further described,there is provided a backwater valve, comprising a valve body, and avalve member pivotally movable about a pivot axis between a normallyopen position away from the valve body and a closed position coveringthe valve body. A counterweight maintains the valve member in thenormally open position. A float is in communication with the valvemember by a control linkage. The float pivots the valve member betweenthe open position and the closed position as it moves vertically.

According to another aspect, the counterweight may be connected to thefloat. The float may be carried toward the bottom of the counterweight,and the float may be connected to the valve member via thecounterweight.

According to another aspect, the control linkage may comprise matingprofiles carried by the valve member and the float.

According to another aspect, the control linkage may be a rigid linkagepivotally linked between the float and the valve member.

According to another aspect, there may be a flange on a bottom of thevalve body between the float and the inlet.

During servicing and testing these is an advantage to being able to moveand, preferably, lock the valve member in the closed position. Thisenables servicing or testing to be performed without concern about waterflowing through the valve. It also allows for plumbing snakes and otherdevices to be inserted through the valve without the valve memberinterfering. Two locking mechanisms will hereinafter be described. Onelocking mechanism has a manual external activator that is connected tothe control linkage to impart movement of the valve member to the closedposition. Another locking mechanism has a movable pressure member theexerts a force upon the valve member to lock the valve member in aclosed position. A manual external locking activator is provided to movethe pressure member between a locking position and a release position.

DESCRIPTION OF THE DRAWINGS

These and other features will become more apparent from the followingdescription in which reference is made to the appended drawings, thedrawings are for the purpose of illustration only and are not intendedto in any way limit the scope of the invention to the particularembodiment or embodiments shown, wherein:

FIG. 1 is a side elevation view in section of a backwater valve.

FIG. 2 is a top plan view in section of the backwater valve.

FIG. 3 is a detailed side elevation view of the float and controllinkage with the valve member in the open position.

FIG. 4 is a detailed side elevation view of the float and controllinkage with the valve member in the closed position.

FIG. 5 is a detailed side elevation view of the float and alternativecontrol linkage.

FIG. 6 is a detailed side elevation view of the float and a furtheralternative control linkage.

FIG. 7 is a detailed side elevation view of the control linkage lockingthe valve member in the closed position.

FIG. 8 is a side elevation view in section of an alternative embodimentof a backwater valve.

FIG. 9 is a detailed side elevation view of the control linkage for abackwater valve which is normally closed.

FIG. 10 is a detailed side elevation view of the control linkage for abackwater valve connected to a manual external activator that can impartmovement to the valve.

FIG. 11 is a side elevation view of a variation of the backwater valvewith a locking mechanism in the locked position.

FIG. 12 is a side elevation view of the variation shown in FIG. 11 withthe locking mechanism in the released position.

DETAILED DESCRIPTION

A first embodiment of a backwater valve generally identified byreference numeral 10 will now be described with reference to FIGS. 1-7.A second embodiment of a backwater valve generally identified byreference numeral 100 will then be described with reference to FIG. 8.

Structure and Relationship of Parts:

Referring to FIG. 1, backwater valve 10 has a hollow valve body 12having an inlet 14, an outlet 16, a top 17 and a bottom 18. A valvemember 20 is pivotally movable between a normally open position (shownin solid lines) away from, or above, inlet 14, such as along top 17 ofvalve body 12, and a closed position covering inlet 14 (shown in brokenlines). Valve body 12 preferably has a cleanout port 19 and atransparent top panel 21 to more easily observe the normal operation ofbackwater valve 10 without having to disassemble it.

Valve member 20 has a pivot end 22 and a remote end 24. Valve member 20has a counterweight 26 attached to pivot end 22 that maintains valvemember 20 in the normally open position. Counterweight 26 is preferablydesigned to be slightly heavier than what is necessary to balance valvemember 20 about its pivot axis 29, in order to maintain the normallyopen position. Referring to FIGS. 3 and 4, a float 28 is connected tovalve member 20 by a control linkage 30, such that float 28 causes valvemember 20 to pivot between the open position (shown in FIG. 3) and theclosed position (shown in FIG. 4) as it moves vertically. Referring toFIG. 2, while float 28 and control linkage 30 is shown on only one side,it may be preferably to have a closing force applied to either side ofvalve member 20. In the discussion herein, it will be understood thatsimilar principles may be used to design such an embodiment.

In some embodiments, the counterweight may be attached to, or integrallyformed with, valve member 20 on the other side of the pivot axis 29, asshown in FIG. 6. In the embodiment depicted in FIG. 3, counterweight 26is the connection between float 28 and valve member 20, where float 28is carried toward the bottom of counterweight 26, and valve member 20 isengaged to the top of counterweight 26. If this weight is insufficient,or if it is desired to distribute the weight differently, counterweight26 may be made up of various components supported in differentlocations, and may be carried by float 28, for example.

As depicted, control linkage 30 is a pair of mating surfaces, such as asprocket 32 and a gear profile 34. Other mating surfaces may also beused, including surfaces that mate by friction. Other types of controllinkages 30 may also be used. One example is shown in FIG. 5, and ismade up of a rigid linkage 36 that is pivotally connected tocounterweight 26. As float moves upward, rigid linkage 36 will causevalve member 20 to rotate closed. In another example, control linkage 30may be an elongate flexible linkage, where tension is provided whenfloat 28 is lowered, and released when float 28 is raised, which allowsvalve member 20 to close under its own weight. Alternatively, controllinkage 30 may not be directly attached to valve member 20. For example,referring to FIG. 6, float 28 may be positioned below an extension ofvalve member 20, such that as it moves upward, float 28 pushes valvemember 20 closed. In this embodiment, counterweight 26 must be carriedby valve member 20. Referring to FIGS. 3 and 4, it will be understoodthat a guide 31 may be required to ensure the proper movement of controllinkage 30 and float 28.

Referring to FIG. 7, one advantage of using the sprocket 32 and gearprofile 34 design is the ability to lock valve member 20 in the closedposition. The valve member 20 may be held closed while linkage 30 isdisengaged, and re-engaged in the lowered position. Valve body 20 is nolonger able to close, as linkage 30 and float 28 are unable to movedownward to allow this to occur. Other designs may also be used toprovide a lock for valve member 20.

It is preferred to design backwater valve 10 to reopen once float 28returns to its normal position. When control linkage 30 is attached tovalve member 20, this generally occurs as a matter of course. However,when there is no attachment, other design approaches may be taken, suchas by having valve member 20 carry counterweight 26, which would apply arestoring force.

Referring to FIGS. 1 and 2, backwater valve 10 may have a flange 38 thatisolates float 28 from the normal flow of water through valve 10. Flange38 is mounted on bottom 18 of valve body 12 between float 28 and inlet14. As water flows between inlet 14 and outlet 16, flange 38 directs themajority of flow away from float 28 to prevent an unnecessary closing ofvalve body 20, and to also prevent debris from interfering with itsnormal operation. In the event of a backflow of water, water will enteroutlet 16 and will not be prevented from reaching float 28 by flange 38.This will cause float 28 to rise, and close valve member 20.Alternatively, float 28 may be isolated from the normal flow of water bysimply positioning it higher than the normal level of water.

Referring to FIG. 8, another embodiment of a backwater valve,represented by reference numeral 100, is shown. Backwater valve 100 isintended to be installed at the end of a line, for example, at theoutlet of a flow pipe into a storage tank to prevent backflow from thestorage tank into the flow pipe. Backwater valve 100 has a valve body102, and valve member 20 opens and closes as described above. Thevariations discussed with respect to FIGS. 1-7 are also applicable tothis embodiment. Valve body 102 has a circumferential flange 104 thatmay be provided for convenience during manufacturing, and that may actas an installation guide. Valve body 102 also has a cylindrical flange106 that extends outward. Cylindrical flange 106 may be used to mount toa pipe, either internally or externally. Alternatively, cylindricalflange 106 may not be present, and valve body 102 may attach directly toa tank wall using pin fasteners, adhesive, or the like.

Operation:

Referring to FIGS. 1 and 2, backwater valve 10 is installed to allowwater to flow from inlet 14 to outlet 16. If the flow of water reversesto flow from outlet 16 to inlet 14, the rising fluid level will causefloat 28 to lift. As float 28 lifts, control linkage 30 causes or allowsvalve body 20 to pivot to the closed position. Valve body 20 is held inthe closed position by the upward pressure from float 28 as well as bythe water pressure from outlet 16. When the water level recedes and flowout outlet 16, float 28 will move downward, and preferably allow valvemember 20 to return to its normally open position as it is acted upon bythe counterweight, the control linkage 30, or both.

Variations:

Referring to FIG. 9, there is illustrated a backwater valve in which thevalve member 20 is in a normally closed position. When valve member 20is in the normally closed position, there is no need for a float andonly counterweight 26 is attached to control linkage 30. Counterweight26 serves a function of reducing a force threshold necessary to beexerted by water to move valve member 20 from the closed position to theopen position, thereby increasing the sensitivity of valve member 20.

Referring to FIG. 10, there is illustrated a manual external activator128 that is connected to control linkage 30 to impart movement of valvemember 20.

Referring to FIGS. 11 and 12, there is illustrated a preferred lockingmechanism. A movable pressure member in the form of a bar 130 slides upalong a track in the form of a channel 132 parallel to valve member 20′when in the closed position. As bar 130 moves along channel 132 itexerts a force upon valve member 20′ which both urges valve member 20′into the closed position and upon continued movement locks valve member20′ in the closed position. A manual external locking activator 134 isprovided to move bar 130 along channel 132 between a locking positionand a release position.

In this patent document, the word “comprising” is used in itsnon-limiting sense to mean that items following the word are included,but items not specifically mentioned are not excluded. A reference to anelement by the indefinite article “a” does not exclude the possibilitythat more than one of the element is present, unless the context clearlyrequires that there be one and only one of the elements.

It will be apparent to one skilled in the art that modifications may bemade to the illustrated embodiments without departing from scope of theClaims.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:
 1. A backwater valve,comprising: a hollow valve body having an inlet and an outlet; a valvemember pivotally movable about a pivot axis between an open position inwhich the valve member is away from the inlet and a closed position inwhich the valve member directly engages and covers the inlet to preventfluid flow through the inlet, the pivot axis being disposed above theinlet; a counterweight in communication with the valve member thatbiases the valve member toward a normally open position above the inlet,the counterweight moving toward a top of the hollow valve body as thevalve member moves toward the closed position; and a float incommunication with the valve member that closes the valve member in thepresence of water, the float moving toward a top of the hollow valvebody as the valve member moves toward the closed position.
 2. Thebackwater valve of claim 1, further comprising a control linkage that ismovable about the pivot axis and positioned opposite the valve memberrelative to the pivot axis.
 3. The backwater valve of claim 2, whereinthe control linkage is connected to the valve member.
 4. The backwatervalve of claim 3, wherein, in the absence of water, the float is spacedbelow the control linkage, and in the presence of water, the float israised to engage the control linkage and close the valve member.
 5. Thebackwater valve of claim 3, wherein the counterweight communicates withthe valve member via the control linkage.
 6. The backwater valve ofclaim 5, wherein the control linkage further comprises a pivotalconnection between a rigid linkage and the counterweight.
 7. Thebackwater valve of claim 6, wherein the pivotal connection between therigid linkage and the counterweight is spaced from the pivot axis of thevalve member.
 8. The backwater valve of claim 1, wherein thecounterweight is attached to or integrally formed with the valve member.9. The backwater valve of claim 1, wherein the float directly engagesthe valve member to close the valve member in the presence of water. 10.The backwater valve of claim 9, wherein, from the normally openposition, the float pivots the valve member to the closed position asthe float moves toward the top of the hollow valve body, the floatexerting a closing force upon the valve member.
 11. The backwater valveof claim 1, wherein the float engages the counterweight as the floatmoves toward a top of the hollow valve body, the float lifting thecounterweight as it closes the valve member.
 12. The backwater valve ofclaim 1, wherein the counterweight is positioned opposite the valvemember relative to the pivot axis.
 13. The backwater valve of claim 1,wherein the float is spaced from a flow path between the inlet and theoutlet.
 14. The backwater valve of claim 13, further comprising a flangeon a bottom of the hollow valve body between the float and the inlet,the flange being positioned to isolate the float from the normal flow ofwater along the flow path.
 15. The backwater valve of claim 1, whereinat least the counterweight is disengagable from the valve member tochange an operation of the valve member from a normally open positionabove the inlet to a normally closed position covering the inlet. 16.The backwater valve of claim 1, wherein the float is connected to thecounterweight.
 17. The backwater valve of claim 16, wherein the float isattached toward a bottom of the counterweight.
 18. The backwater valveof claim 2, wherein a manual external activator is connected to thecontrol linkage to impart movement of the valve member.
 19. Thebackwater valve of claim 2, wherein the control linkage comprises matingprofiles carried by the valve member and the float.
 20. The backwatervalve of claim 2, wherein the control linkage is flexible or rigid.